where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -
922 views
Technical Discussions
Louis Bastarache
Louis Bastarache
02:37 Nov-06-2005
Search unit

Hi everybody,

I just got my new search unit of one inch large but now I need to know if i can check my sound entry point with the IIW block "type one" and if not what should i do?

Thanks


    
 
 Reply 
 
Nigel Armstrong
Engineering, - Specialist services
United Kingdom, Joined Oct 2000, 1096

Nigel Armstrong

Engineering, - Specialist services
United Kingdom,
Joined Oct 2000
1096
01:10 Nov-11-2005
Re: Search unit
Its been a week since you posted, so I hope you managed to check the probe's emission index, Louis.

You do not specify exactly which type of probe you have, but lets say its a 2MHz 1" diameter, 60 deg shearwave. The IIW block (V1) is 25mm thick with a radius of 100mm. This should be ideal for checking the beam emission (index) point. If you are concerned about the probe housing being larger than the block thickness, put two blocks together, they make a 50 mm thcickness..

Best regards

Nigel

----------- Start Original Message -----------
: Hi everybody,
: I just got my new search unit of one inch large but now I need to know if i can check my sound entry point with the IIW block "type one" and if not what should i do?
: Thanks
------------ End Original Message ------------




    
 
 Reply 
 
Udo Schlengermann
Consultant, -
Standards Consulting, Germany, Joined Nov 1998, 177

Udo Schlengermann

Consultant, -
Standards Consulting,
Germany,
Joined Nov 1998
177
01:27 Nov-14-2005
Re: Search unit
reply by Udo Schlengermann:

Two effects cause unacceptable inaccuracies when checking large sized angle-beam-probes on the IIW calibration block (25 mm thick, 100 mm quadrant):

1. side-wall reflections have influence on the pulse shape, i.e. on the maximum echo. So the position of maximum echo amplitude will not necessarily be the one where the beam hits the quadrant surface radially.

2. depending on the frequency the near-field length of a large probe may be larger than the radius of the quadrant (100 mm). Then the maxium echo is disturbed by near-field interferences. So determination of the index point (and beam angle) may be not correct.

Contrary to the reply by Nigel Armstrong, I cannot recommend the use of two parallel 25-mm-blocks, because the interface between the blocks will still cause side wall reflections.

Because of these reasons European Standard EN 12223 on block no 1 allows for modifications (thicker blocks).
European Standard 12668-2 for verfication of probes in annex B for example shows a modification with a thickness of 100 mm.

If your probe has a nearfield in steel larger than 100 mm, you have to use special blocks with a radius larger than that nearfield. Only then the axis of the beam hits the quadrant suface radially at the point of maximum echo amplitude.
Manufacturer's verification has to use blocks with radius up to 200 mm , as required by EN 12668-2.

Kind regards
Udo Schlengermann
Applications Laboratory
GE Inspection Technologies GmbH
Huerth, Germany


----------- Start Original Message -----------
: Hi everybody,
: I just got my new search unit of one inch large but now I need to know if i can check my sound entry point with the IIW block "type one" and if not what should i do?
: Thanks
------------ End Original Message ------------




    
 
 Reply 
 
Nigel Armstrong
Engineering, - Specialist services
United Kingdom, Joined Oct 2000, 1096

Nigel Armstrong

Engineering, - Specialist services
United Kingdom,
Joined Oct 2000
1096
04:12 Nov-15-2005
Re: Search unit
I stand corrected. A practice derived from that usual problem out in the field - lack of resources. Thank you, Udo, for your clear explanation. I shall tell my employers: "Give me the right tools and I shall do my best to give give you a quality result."


    
 
 Reply 
 

Product Spotlight

Echomac® Small

Available with up to eight channels of electronics to detect and evaluate thickness, flaws and eccen
...
tricity, this UT tester is housed in a convenient, smaller cabinet. This instrument can be used in conjunction with bubbler or immersion tank systems, or with a test bench or in laboratory applications. The Echomac® Small is available in the FD4, FD6 or FD6A versions.
>

Aerospace Systems - Automated Ultrasonic Inspection

USL are specialists in the design and manufacture of turnkey ultrasonic inspection systems for aer
...
ospace applications. From monolithic composites to complex honeycomb structures. This video shows just a few examples of what is possible, find out more at: www.ultrasonic-sciences.co.uk
>

SONOAIR - air-coupled Phased Array Ultrasonic Inspection System

For highly attenuating materials, the performance of the system is critical. The ultrasonic sensors,
...
the scanning area and the system settings should be flexibly adapted to the test task and the material. These high expectations are met with the new and modular testing system SONOAIR. With the world’s first air-coupled phased-array UT inspection system SONOAIR we developed a technology that works with up to 4 transmitter and receiver channels with freely configurable square wave burst transmitters as wells as low noise receiving amplifiers.
>

Combination of Digital Image Correlation and Thermographic Measurements

The combination of measuring results from the digital image correlation (ARAMIS, DIC) and temperat
...
ure measuring data from infrared cameras permits the simultaneous analysis of the thermal and mechanical behavior of test specimens in the materials and components testing field.
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window